Converting of hydrocarbons



Oct. 14, 1930. L. KIRSCHBRAUN CONVERTING OF HYDROCARBONS Original Fi-led Nov 17 flam @M WW Patented Oct. 14, 1930 UNITED STATES PATENT OFFICE LESTER KIRSCHIBRAUN, OF CHICAGO, ILLINOIS, ASSIGNOR TO UNIVERSAL OIL PROD- UCTS COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF SOUTH DAKOTA CONVERTING- OF HYDROCARBONS Application filed November 17, 1920, Serial No. 424,592. Renewed December 27, 1924.

This invention relates to the converting of hydrocarbons and refers more particularly to the molecular rearrangement taking place, due to the imposition of definite conditions of heat and pressure whereby the lighter constituents are extracted therefrom and the residual material treated to obtain therefrom any low boiling point fractions remaining therein.

Among its salient objects are to provide a process for the converting of hydrocarbon oil whereby the conditions of heat and pressure in the heating and vaporizing zones are regulated to vaporize a substantial portion of the lighter fractions; to provide a process in which the higher boiling point cuts contained in the residual material are treated separately while in a heated state with incondensible gas whereby additional distillate containing lighter fractions may be obtained therefrom, and to provide a process which permits of the extraction of an increased quantity of convertible distillate and one n which the heat of the residual substances is requisitioned and with the addition of gas used to further convert this residual hydrocarbon oil.

The single figure is an elevational side View of the apparatus used in connection with this process.

Referring to the drawingsin the furnace 1, which is heated by means of a gas burner 2, are mounted a series of heating coils 3, which are connected to a vapor chamber 4 by means of a pipe 5. Into the top of the vapor chamber is tapped a vapor line 6 having a trap 7 interposed therein and connecting the vapor chamber with the water condenser 8. The water condenser in turn is connected by a line 9 to a receiver 10 which is fitted with a liquid gauge 11 and a liquid draw-off pipe 12 controlled by a valve 13. The residual drawoif line 14 from the vapor tank 4, which is controlled by a valve 15, directs the residual oil and condensate from the vapor tank into a. separator 16 through a spray 17. The residual substance, after passing over a series of pans 18 arranged in the interior of the separator, collects in a pool 19 in the bottom of the separator and the heavier portion'may be drawn off through a pipe 20 controlled by a valve 21. In this bottom pool of the dephlegmator 16 is positioned a perforated circular gas pipe 22, which is supplied with incondensible gas under pressure from the receiver 10 through the gas line 23, controlled by the valve 24:. The vapors released from this residual oil in the separator are directed through a vapor line 25 tapped into the top of the separator and, after passing through the water condenser 26, are collected as heavy distillate in the receiver 27, which is equipped with a liquid level gauge 28, a liquid drawolf line 29 regulated by a valve 30 and a gas relief pipe 31 controlled by a valve 32. The valve 15 should be of such character and so adjusted that a lower pressure can be maintained as desired in the separator 16 and the receiver 27 than is maintained in the rest of the system. In the opposite side of this receiving tank 27 is tapped a draw-off line 33, which is controlled by a valve 34 and furnishes a means for directing the heavy dis tillate through the pump 35 to the raw oil charging line 36 through the connecting line 37 in which is interposed a check valve 38. A vertical reflux line 39 regulated by a valve 40 relieves the trap 7 of any condensate which may collect therein and returns it to the line 36 connected to the heating coils 3.

The operation of the process is as follows: The raw oil is introduced from any convenient source through the charging line 41 and, after passing through the pipe 36 where it may combine with the reflux or heavy distillate, it is charged to the heating tubes where it is raised to a cracking temperature under substantial pressure. The cracked fluid oil, after passing through a line 5, collects in the vapor chamber or reacting zone 4 where a substantial portion of the liquid oil is released as vapor. This vapor is drawn oif from the top of the vapor chamber through the line 6 and is collected in the receiver 10 after passin through the water condenser 8. Any retlux collecting in the vapor line 6 may be returned to be recharged to the heating coils through the reflux line 39. The heavier or higher boiling point hydrocarbons with the residual substance, which collects in the vapor chamber, is drawn off and introduced into the top of the separator 16 where it is sprayed in order that it may be thoroughly broken up in its passage therethrough. While passing through the separator and after collecting in the bottom in the pool 19, this heavy oil is subjected to the vaporizing effect of the incondensible gas, which is drawn from the top of the receiver and introduced into the bottom pool of the separator where it is caused to bubble up under a substantial pressure through the body of the oil. It is thereby thoroughly mixed with the residual substance, which is in a finely divided form while passing over the successive pans or baflles in the separator, being sprayed into the top thereof. The condensible vapors, which are released from the residual substance, due to the effect of this introduction of gas, pass from the top of the separator and are collected in the reservoir 27 after being condensed in the water condenser 26. The amount of heavier distillate, which may be released from the residual oil drawn from the vapor chamber, is considerable, this heavy distillate comparing favorably in its gravity and other physical and chemical characteristics with the gas oil or raw oil charge originally treated. The heavier sludge, which is the resultant product after treatment of the residual substance with the incondensible gas, is drawnofi' through the pipe 20 while the heavy distillate collecting in the receiver 27 may be taken from the line 29 or directed back Into the system through the connecting pipe 33 and pump 35.

An illustrative run on this process follows: Treating Kansas gas oil having a gravity of approximately 32 B. and heating the same to a temperature of 800 to 900 F. and a v pressure of 100 to 150 pounds, the residual substance drawn from the vapor tank is at a temperature of approximately 700 to 760 F. with a gravity of from 16 to 20 B. By means of this process in the neighborhood of 60% of the residuum may be distilled off,

drocarbons are produced therefrom, condensing and collecting the lighter fraction, and

directing the residual substances unvapor-- ized during the cracking reaction to a separate receptacle maintained under a lower pressure than that to which the oil was previously subjected and wherein no rise in oil temperature occurs and there injecting into the body of oil incondensible gas produced during the cracking and under substantial pressure.

2. In an apparatus for converting hydrocarbons, the combination with connecting heating and vaporizing means in which the top of said receptacle to flow over the baflles,

a gas line leading from the collecting means for injecting gas into the separate residual Oll. receptacle, anda second condensing means connected to said separate residual oil receptacle for condensing the condensible vapors therefrom. U

3. In an apparatus for converting hydrocarbons, the combination with connecting heating and vaporizing means in which the hydrocarbons are subjected to temperature and pressure conditions for cracking a substantial quantity of the oil, condensing and collecting means connected to said vaporizing means, of a separate unheated receptacle connected to the vaporizing means and means for, passing residual oil from the vaporizing means to said separate unheated receptacle, a gas line leading from the collecting means for directing the incondensible gases generated during the operation of the process to the separate receptacle and there injecting them into the body of oil, a second condensing and collecting means connected with the separate receptacle for condensing the vapors re leased therein, and means for returning the distillate extracted from the residual hydrocarbons to be retreated in the heating means.

4. A continuous method of treating hydrocarbon oil, consisting in subjecting the oil to cracking conditions of temperature and pressure. to cause substantial conversion thereof, separately removing the vaporized and unvaporized portions of the oil, condensing the cracked vapors and collecting the distillate and incondensible gas, passing the unvaporized oil constituents to an enlarged zone maintained under a reduced pressure and injecting a portion of such incondensible gas into the body of unvaporized oil constituents in said enlarged zone to cause substantially distillation of such constituents.

5. A continuous method of treating hydrocarbon oil, consisting in subjecting the oil to cracking conditions of temperature and pressure to cause substantial conversion thereof, separately removing the vaporized and unvaporized portions of the oil, condensing the cracked vapors and collecting the distillate and incondensible gas, passing the unvaporized oil constituents to an enlarged zone maintained under a reduced pressure and injecting a portion of said incondensible gas into the body of unvaporized oil constituents in said enlarged zone to cause substantial distillation of such constituents, as secondary vapors, and separately condensing and collecting such secondary vapors.

6. A continuous method of treating hydrocarbon oil,- consisting in subjecting the oil to cracking conditions of temperature and pressure to cause substantial conversion thereof, separately removing the vaporized and unvaporized portions of the oil, condensing the cracked vapors and collecting the distillate and incondensible gas, passing the unvaporized oil constituents to an enlarged zone maintained under a reduced pressure and injecting incondensible gas into the body of unvaporized oil constituents in said enlarged zone to cause substantial distillation of such constituents, accelerating such distillation by spraying the residual oil in at the top of said enlarged zone and causing it to descend a tortuous path countercurrent to the ascending gases.

7. A hydrocarbon oil cracking process which comprises subjecting the oil to cracking conditions of temperature and superatmospheric pressure to produce lower boiling point products, separating vaporized portions of the oil from unvaporized portions thereof, condensing said vaporized portions, passing said unvaporized portions to an enlarged zone maintained under reduced pressure thereby effecting distillation in said zone, injecting hydrocarbon gas into the oil in said zone to assist the distillation therein, and subjecting portions of the oil vaporized in said zone to recracking to produce additional lower boiling point products.

LESTER KIRSCHBRAUN. 

